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Carriers in astrophysics

A peculiarity of astrophysic research is the necessary combination of approaches or methods to answer a given question. Usually, observations are compared to models themselves based on specific theoretical developments. In some instances, laboratory experimentation is also required to derive conclusions.

IPAG is a laboratory of exceptional richness for all the aspects detailed below are present, fostering interactions between people involved mainly in astrophysical observations, experimentations, modelling, instrumental developments, and theoretical aspects. As such, IPAG provides the needed elements for the emergence of original ideas and scientific breakthroughs.

Observations : IPAG is involved in observational programs using world leading facilities. Those observations cover a broad range of energy, from neV to several tens of TeV. Observational astrophysics requires cutting-edge instruments, some of which being designed and/or developed at IPAG.

Modelling / numerical simulation : a model is a representation of the studied object, where only the subset of the dominant physical and chemical process are considered. These models aimed at being compared with observations, and may also have a predictive power and call for follow-up observations.

Theory : provides a detailed and complete explanation of the phenomena from the basic principles of physics. When this is not possible, the result is a challenge or even a crisis of these fundamental principles. This is how science progresses.

Instrumentation : develop, build, install, test, and make use of new instruments. The instrumentation is made ​​possible through the sharing of a large number of skills (technical, engineering, theory, etc.). Instruments are in contsant renewal and are at the forefront of technology. These developments often lead to some everyday life applications.

Numerical Experimentation : Numerical Experimentation has become essential nowadays. It aims at treating, in the most precise and robust ways, the processes involved in a model. The predictive power of the numerical experimentation has become indispensable today to reinforce certain assumptions or intuitions. Think that what we see is a projection of the Universe in two dimensions, and it is sometimes a major difficulty to recover to the three-dimensional structure of the underlying objects. This is a case where the numerical simulations come to our aid.

Laboratory experimentation : in this case , the experiment is very real . This may be the synthesis of molecules to the ice surface of interstellar grains or interplanetary dust and meteorites composition. In another genre, we can also study the bombardment of interstellar grains kind of particles of high energy. If in the first case , the experience can be installed in a laboratory of modest size, the second type of experiment requires the use of large instruments (eg « Soleil » in Orsay or the ESRF in Grenoble).

How to work in astrophysics

As one might expect from the above description, the pathways to astrophysics are extremely varied, reflecting the diversity of professions and skills encountered in an institute like IPAG. So there is no one way to go. However, we may be able to identify trends according to the type of activity you’re aiming at. For example it is quite common to see instrumentalists without a particular knowledge of the astrophysical objects the instrument will allow to study. The corollary is also true : astrophysicists often do not know in details how the instrument which provided the observations does work. We may draw two broad categories : those people who will study the objects and not the instruments, and the opposite. In the first case, a solid background in fundamental physics is required. In the second, a strong background in instrumental physics is required.